/* ----------------------------------------------------------------------
* Copyright (C) 2010 ARM Limited. All rights reserved.
*
* $Date:        15. February 2012
* $Revision: 	V1.1.0
*
* Project: 	    CMSIS DSP Library
* Title:	    arm_mat_add_q31.c
*
* Description:	Q31 matrix addition
*
* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
*
* Version 1.1.0 2012/02/15
*    Updated with more optimizations, bug fixes and minor API changes.
*
* Version 1.0.10 2011/7/15
*    Big Endian support added and Merged M0 and M3/M4 Source code.
*
* Version 1.0.3 2010/11/29
*    Re-organized the CMSIS folders and updated documentation.
*
* Version 1.0.2 2010/11/11
*    Documentation updated.
*
* Version 1.0.1 2010/10/05
*    Production release and review comments incorporated.
*
* Version 1.0.0 2010/09/20
*    Production release and review comments incorporated.
*
* Version 0.0.5  2010/04/26
*    incorporated review comments and updated with latest CMSIS layer
*
* Version 0.0.3  2010/03/10
*    Initial version
* -------------------------------------------------------------------- */

#include "arm_math.h"

/**
 * @ingroup groupMatrix
 */

/**
 * @addtogroup MatrixAdd
 * @{
 */

/**
 * @brief Q31 matrix addition.
 * @param[in]       *pSrcA points to the first input matrix structure
 * @param[in]       *pSrcB points to the second input matrix structure
 * @param[out]      *pDst points to output matrix structure
 * @return     		The function returns either
 * <code>ARM_MATH_SIZE_MISMATCH</code> or <code>ARM_MATH_SUCCESS</code> based on the outcome of size checking.
 *
 * <b>Scaling and Overflow Behavior:</b>
 * \par
 * The function uses saturating arithmetic.
 * Results outside of the allowable Q31 range [0x80000000 0x7FFFFFFF] will be saturated.
 */

arm_status arm_mat_add_q31(
    const arm_matrix_instance_q31* pSrcA,
    const arm_matrix_instance_q31* pSrcB,
    arm_matrix_instance_q31* pDst)
{
	q31_t* pIn1 = pSrcA->pData;                    /* input data matrix pointer A */
	q31_t* pIn2 = pSrcB->pData;                    /* input data matrix pointer B */
	q31_t* pOut = pDst->pData;                     /* output data matrix pointer */
	q31_t inA1, inB1;                              /* temporary variables */

#ifndef ARM_MATH_CM0

	q31_t inA2, inB2;                              /* temporary variables */
	q31_t out1, out2;                              /* temporary variables */

#endif //      #ifndef ARM_MATH_CM0

	uint32_t numSamples;                           /* total number of elements in the matrix  */
	uint32_t blkCnt;                               /* loop counters */
	arm_status status;                             /* status of matrix addition */

#ifdef ARM_MATH_MATRIX_CHECK

	/* Check for matrix mismatch condition */
	if((pSrcA->numRows != pSrcB->numRows) ||
	        (pSrcA->numCols != pSrcB->numCols) ||
	        (pSrcA->numRows != pDst->numRows) || (pSrcA->numCols != pDst->numCols)) {
		/* Set status as ARM_MATH_SIZE_MISMATCH */
		status = ARM_MATH_SIZE_MISMATCH;
	} else
#endif
	{
		/* Total number of samples in the input matrix */
		numSamples = (uint32_t) pSrcA->numRows * pSrcA->numCols;

#ifndef ARM_MATH_CM0

		/* Run the below code for Cortex-M4 and Cortex-M3 */

		/* Loop Unrolling */
		blkCnt = numSamples >> 2u;


		/* First part of the processing with loop unrolling.  Compute 4 outputs at a time.
		 ** a second loop below computes the remaining 1 to 3 samples. */
		while(blkCnt > 0u) {
			/* C(m,n) = A(m,n) + B(m,n) */
			/* Add, saturate and then store the results in the destination buffer. */
			/* Read values from source A */
			inA1 = pIn1[0];

			/* Read values from source B */
			inB1 = pIn2[0];

			/* Read values from source A */
			inA2 = pIn1[1];

			/* Add and saturate */
			out1 = __QADD(inA1, inB1);

			/* Read values from source B */
			inB2 = pIn2[1];

			/* Read values from source A */
			inA1 = pIn1[2];

			/* Add and saturate */
			out2 = __QADD(inA2, inB2);

			/* Read values from source B */
			inB1 = pIn2[2];

			/* Store result in destination */
			pOut[0] = out1;
			pOut[1] = out2;

			/* Read values from source A */
			inA2 = pIn1[3];

			/* Read values from source B */
			inB2 = pIn2[3];

			/* Add and saturate */
			out1 = __QADD(inA1, inB1);
			out2 = __QADD(inA2, inB2);

			/* Store result in destination */
			pOut[2] = out1;
			pOut[3] = out2;

			/* update pointers to process next sampels */
			pIn1 += 4u;
			pIn2 += 4u;
			pOut += 4u;

			/* Decrement the loop counter */
			blkCnt--;
		}

		/* If the numSamples is not a multiple of 4, compute any remaining output samples here.
		 ** No loop unrolling is used. */
		blkCnt = numSamples % 0x4u;

#else

		/* Run the below code for Cortex-M0 */

		/* Initialize blkCnt with number of samples */
		blkCnt = numSamples;


#endif /* #ifndef ARM_MATH_CM0 */

		while(blkCnt > 0u) {
			/* C(m,n) = A(m,n) + B(m,n) */
			/* Add, saturate and then store the results in the destination buffer. */
			inA1 = *pIn1++;
			inB1 = *pIn2++;

			inA1 = __QADD(inA1, inB1);

			/* Decrement the loop counter */
			blkCnt--;

			*pOut++ = inA1;

		}

		/* set status as ARM_MATH_SUCCESS */
		status = ARM_MATH_SUCCESS;
	}

	/* Return to application */
	return (status);
}

/**
 * @} end of MatrixAdd group
 */
